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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

It’s just not fair, you know? Because climate deniers only have so many myths they can keep trotting out again and again, and meanwhile the science just keeps gettingmore science-y. How are you supposed to compete with that?

The answer, my friend, is to shout louder. Here are some places to start:

A Hiatus on “Hiatus”

On Thursday (June 4) a new study led by the director of the leading U.S. climate data center was the latest to show evidence that global warming is—shocker—continuing. My Slate colleague Phil Plait has more, but the main point is: Talk of a “hiatus” in climate change has gotten blown way out of proportion.

From the study:

The central estimate for the rate of warming during the first 15 years of the 21st century is at least as great as the last half of the 20th century. These results do not support the notion of a “slowdown” in the increase of global surface temperature.

The study appeared in Science, one of the most prestigious scientific journals, and was accompanied by a press conference from the National Oceanic and Atmospheric Administration—both rare for what was essentially a routine update in a widely used global temperature data set.

Climate change not on hiatus, new research shows

“There’s no slowdown in global warming.”

That comes from Russell Vose, of the National Oceanic and Atmospheric Administration, and a team of scientists from the agency’s National Centers for Environmental Information, who found that unlike reports in recent years of a “climate change hiatus,” global temperature trends are still creeping upwards. In other words, there’s been no halt. The scientists published their findings Thursday, June 4, in the journal Science.

“We are not the first ones to do any of this work,” Vose told weather.com, referring to the extensive analyses conducted by the Intergovernmental Panel on Climate Change and the accompanying reports. But, he noted, his team had a few datasets not yet available when the IPCC published its fifth — and most recent — assessment in 2013.

The adjustments to the data were slight, but removed a flattening of the graph this century that has led climate sceptics to claim the rise in global temperatures had stopped.

“There is no slowdown in warming, there is no hiatus,” said lead author Dr Tom Karl, who is the director of Noaa’s National Climatic Data Centre.

Dr Gavin Schmidt, a climatologist and the director of Nasa’s Goddard Institute for Space Studies said: “The fact that such small changes to the analysis make the difference between a hiatus or not merely underlines how fragile a concept it was in the first place.”

The results, published on Thursday in the journal Science, showed the rate of warming over the past 15 years (0.116C per decade) was almost exactly the same, in fact slightly higher, as the past five decades (0.113C per decade).

Global warming's great hiatus gets another debunking

The long-debated hiatus or pause in global warming, championed by climate denialists who tried to claim it proved scientists' projections on climate change are inaccurate or overblown, probably did not happen at all.

A new study by researchers at the National Oceanic and Atmospheric Administration finds that the world’s warming never really stalled during the last 15 years—it was just masked by incomplete data records that have been improved and expanded in recent years.

"The rate of temperature increase during the last half of the 20th century is virtually identical to that of the 21st century," said Tom Karl, director of NOAA's National Centers for Environmental Information and lead author of the study.

Here’s why the global warming hiatus might not exist

The global warming hiatus — a decade-plus slowdown in warming — could be chalked up to some buoys, a few extra years of data and a couple buckets of seawater.

That’s the finding of a new study published on Thursday in Science, which uses updated information about how temperature is recorded, particularly at sea, to take a second look at the global average temperature. The findings show a slight but notable increase in that average temperature, putting a dent in the idea that global warming has slowed over the past 15 years, a trend highlighted in the most recent Intergovernmental Panel on Climate Change report.

The term “ global warming hiatus” is a bit of a misnomer. It refers to a period of slower surface warming in the wake of the 1997-98 super El Niño compared to the previous decades. However, make no mistake, the globe’s average temperature has still risen over that period (including record heat in 2014) and temperatures now are the hottest they’ve been since recordkeeping began in the 1880s. So let’s call it what it really is: a slowdown, not a disappearance of global warming.

Improved data set shows no global warming ‘hiatus’

National and international studies have shown that the Earth is warming, and with this warming, other changes are occurring, such as an increasing incidence of heat waves, heavy downpours and rising sea levels.

In its Fifth Assessment Report in 2013, the Intergovernmental Panel on Climate Change found that the temperature of the Earth increased at a rate of 0.22 Fahrenheit (0.12 Celsius) per decade from 1951-2012. It also found that the rate of warming from 1998-2012 had slowed to 0.09F (0.05C) per decade.

This slowdown in the rate of warming, called a “hiatus,” was initially perplexing to climate scientists. It was inconsistent with expectations that global temperatures would rise at similar or even greater rates than they had in the latter half of the 20th century as the concentration of greenhouse gases in the atmosphere continued to rise.

In an article published in Science Express on June 4, my colleagues and I at NOAA’s National Centers for Environmental Information (NCEI) presented updated findings that show no hiatus in the rate of warming. Using newly developed data sets of land and ocean temperatures and two additional years of data, we conclude that the global surface temperature increased at a rate of 0.19F (0.106C) per decade from 1998-2014, similar to the rate of 0.20F (0.113C) per decade from 1950-1999.

NOAA temperature record updates and the ‘hiatus’

In a new paper in Science Express, Karl et al. describe the impacts of two significant updates to the NOAA NCEI (née NCDC) global temperature series. The two updates are: 1) the adoption of ERSST v4 for the ocean temperatures (incorporating a number of corrections for biases for different methods), and 2) the use of the larger International Surface Temperature Initiative (ISTI) weather station database, instead of GHCN. This kind of update happens all the time as datasets expand through data-recovery efforts and increasing digitization, and as biases in the raw measurements are better understood. However, this update is going to be bigger news than normal because of the claim that the ‘hiatus’ is no more. To understand why this is perhaps less dramatic than it might seem, it’s worth stepping back to see a little context…

Science challenges claim that global warming took a hiatus

A reported pause in global warming—a mystery that has vexed scientists and delighted contrarians—was an illusion based on inadequate data, U.S. government researchers reported Thursday.

The findings by National Oceanic and Atmospheric Administration (NOAA) researchers that there was no warming "hiatus" over the past 15 years could reshape consensus science on recent climate change. The research undercuts an argument of pundits and politicians who oppose taking action.

In the new report, NOAA's team focused on an ever changing network of thousands of temperature-monitoring stations on land and on ships and buoys at sea around the world. The scientists replotted average annual surface temperatures since 1880 while accounting for changes and quirks in the readings, particularly anomalies from ocean ships and buoys. Their conclusion confirms that unrelenting warming has occurred since the mid-20th century, according to the study published in the journal Science.

Science publishes new NOAA analysis: Data show no recent slowdown in global warming

A new study published online today in the journal Science finds that the rate of global warming during the last 15 years has been as fast as or faster than that seen during the latter half of the 20th Century. The study refutes the notion that there has been a slowdown or "hiatus" in the rate of global warming in recent years.

The study is the work of a team of scientists from the National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Information* (NCEI) using the latest global surface temperature data.

"Adding in the last two years of global surface temperature data and other improvements in the quality of the observed record provide evidence that contradict the notion of a hiatus in recent global warming trends," said Thomas R. Karl, L.H.D., Director, NOAA's National Centers for Environmental Information. "Our new analysis suggests that the apparent hiatus may have been largely the result of limitations in past datasets, and that the rate of warming over the first 15 years of this century has, in fact, been as fast or faster than that seen over the last half of the 20th century."

Slow-down’ in climate change never happened, says major review

A major review of global temperatures by a leading US Government agency has failed to find support for the view that global warming has slowed down since 1998, as many climate sceptics have repeatedly claimed over the past two decades.

The prestigious US National Oceanographic and Atmospheric Administration (NOAA) has re-evaluated its surface temperature records over land and sea and concluded that the rate of global warming has been just as fast at the start of this century as it was at the end of the last.

NOAA scientists believe that the global warming “hiatus” highlighted in the last report of the UN’s Intergovernmental Panel on Climate Change (IPCC) – and exploited by sceptics to undermine climate change policy – is nothing more than an illusion resulting from artefacts in the data.

Study dismisses "hiatus" in global warming, says temperatures up

An apparent slowdown in the pace of global warming in recent years may be an illusion based on skewed data, according to a study on Thursday that found no break in a trend of rising temperatures.

In 2013, the U.N. panel of climate experts reported a "hiatus" in warming since about 1998, despite rising man-made emissions of greenhouse gases. That heartened sceptics who say the risks of climate change have been exaggerated.

The new U.S. study in the journal Science, based on a re-analysis of worldwide temperature data, found no pause in the warming blamed by most climate experts for producing heatwaves, downpours and higher sea levels.

What you need to know about the NOAA global warming faux pause paper

Last week, a paper out of NOAA concluded that contrary to the popular myth, there’s been no pause in global warming. The study made headlines across the world, including widely-read Guardian stories by John Abraham and Karl Mathiesen. In fact, there may have been information overload associated with the paper, but the key points are relatively straightforward and important.

Whither the pause? NOAA reports no recent slowdown in warming

Mountains of ink have been spilled in recent years on whether or not global warming has paused or slowed down. We’ve discussed it on this site extensively in the past, and numerous studies have examined whether the apparent pause might have been caused by additional ocean heat uptake, small volcanoes, a weak solar cycle,poor arctic coverage in existing datasets, and\or a whole host of other possible explanations.

A new high-profile paper just released in Science by Tom Karl and colleagues at NOAA argues that any slowdown in warming ended (if it ever really existed in the first place) as a result of two simple factors: correctly dealing with temperature readings from buoys, and the passage of time.

In a newly released estimate of global temperatures, they argue that the rate of warming over the past 17 years is no different than that for the prior 50 years, and that there is no apparent pause or slowdown in warming.

That being said, and no discredit to anyone's research on this forum, can we agree that there is still an argument in the data on both sides and continual change in the interpretation of the data in regard to the extent of our limited ability to capture all data?

I think we all agree that the current methods used to estimate the change in the surface temperature metric are, just that, estimates, and that improvements will continue to be made.

However, I dont think you can find a scientist publishing in the field of surface temperature estimation that will argue that temperature is doing anything other than continuing to rise. What "argument" did you have in mind? What change in interpretation?

The global surface temperature metric is extremely important to us - the surface is where we live - but it is not necessarily the best metric for assessing AGW. The energy imbalance is potentially better estimated from ocean temperature change especially now that Argo is deployed. Furthermore ice loss (and thus sealevel) are better integrators of long term climate change. Any argument there?

Mattimus - I must admit to a bit of difficulty in parsing what you are asking. That said, the evidence to date is sufficient to convince the vast majority of scientists studying the subject (the oft-mentioned 97%), and there really isn't any data sufficently strong to consider rejecting AGW. Let alone in favor of any particular theory of the contradictory multitude offered up sans support by the 3%.

Our understanding continually evolves with additional data and examination. But overturning the entire structure of climate science, rather than detailing particulars, would require both quite extraordinary evidence for a new cause of climate change, and an entire series of data that rejected all the elements of our current understanding - spectroscopy, radiative physics, satellite observations, GHG fingerprints, sums of forcings, etc.

No such evidence has been presented, and arguments against AGW simply haven't held up.

If your intent is to purport that climate science might radically change because physics radically changed, it won't get you too far. :) Climate science doesn't rest on any single orthodoxy. The evidence comes from vastly disparate sources using numerous ways to measure many different elements of the earth system.

I also wouldnt argue at all with the finding that the surface and ocean temperature are rising over the times discussed. The only piece I'm concerned with is focusing on how much it is caused by human activity. And my only concern in that realm is who that gives an excuse to intervene

Mattimus - I think we can also agree that there are non-climate scientists, and non-scientists who either misunderstand or distort science (or both) to claim there are arguments and uncertainties in climate science where none exist. This site is dedicated to presenting the actual science as an antidote to those. Without specifics about what arguments you mean it is difficult to assess what you mean.

If you think there is disagreements between climate scientists on whether the surface temperature is increasing, then please quote peer-reviewed research to support that.

I hope that we can admit that we are mere witnesses to a greater plan, even speaking just about our planet's cycles/moods. I am a 100% believer in the scientific method but climate science is such a vastly complicated system that we'd need models capable of surpassing the human mind to calculate all it's nuances. That's why we think computer simulations will get us there but we havent come close to mimicking minds via computers. That's the only reason I brought up QM

As you suggested I want to stay on topic and want to ask the basic question if the problem is increased CO2. Why aren't we talking solutions instead of debating? Would anyone disagree with planting more trees to reduce excess CO2? Even taxpayer dollars? I just read an article about the Virgin Mobile CEO giving $25 million to the best idea of absorbing CO2. If we think there's an issue with CO2 why not come up with ideas to reduce it or keep it steady and see if it changes things?

And what informs that opinion? On the contrary, we have published science to quite the contrary. A gross level, for any planet in any solar system, surface temperature is described by the energy balance. It is function of incoming radiation, planetary albedo and atmospheric composition. A planet with atmosphere and oceans has internal variability from being unevenly heated.

However, there is no "cycle or mood" that can steadily increase the ocean heat content. Conservation of energy requires that energy come from somewhere. What cycle is creating energy? The observed change is consistant with change in GHG. Solar is not increasing. You can argue about climate sensitivity or the accuracy of models but you cant argue about conversation of energy.

I came to this site to learn more about this topic. And this site and its contributors, including the ones who respond in the comments, have been very helpful in adding to my understanding of the breadth and depth of the currently developed and continuing to be developed understanding of what is going on.

Though there are many different things you could choose to check out, the "Newcomers Start Here" button at the top of the main page should be the first stop.

However, what I found to be very compelling evidence that human impacts are significant is simply looking at the global average surface temperature data sets using the SkS Temperature Trend Calculator and reviewing the known change of CO2 in the atmosphere (NOAA presentation through this link is a good one). That pair of information reviewed objectively make it very difficult to expect to find another better explanation for what is known to have happened already other than "human impacts", particularly the burning of fossil fuels.

There are indeed many other factors, cyclical as well as random, that can and do temporarily skew the global average surface temperature values from the trend due to human impacts. However, those effects are part of what is now reasonably well understood with better understanding continuing to be developed.

I hope you enjoy exploring the wealth of information and understanding that is available through this resource.

scaddenp, come on man the scientists on this planet have been talking about the 100K+ year cycles of this planet resulting in ice ages and complete melting of the polar caps. Are we disputing their science?

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Moderator Response:

[JH] Unless you provide documentation for your assertions, they are nothing more than your personal opinion which carries very lttle weight on this website. The tone of your comment is also not acceptable.

I apologize for not adding any studies or references to studies to my comments but I truly feel there is no lack of that on this site. I have no doubt that most if not all on this site have several studies that they can point to as a means to prove a point. My only point is this. If we're still arguing about it then we don't have it completely figured out yet. Honestly we're kidding ourselves (and limiting ourselves) if we think we do. I would never encourage anyone to dismiss what they believe in only that they encourage those who have a like or opposing view. It's fun to be here trying to figure stuff out as long as we realize that we're all trying to figure it out and none of us has "the answer". And don't think you're close just because the media in 2015 is on your side. It changes like the climate. :)

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Moderator Response:

[DB] As others have alluded to, just because the jigsaw puzzle of climate change has a piece missing does not mean that the picture of an apple is that of a platypus.

Mattimus, not having all the exact answers to every detail of the climate doesn't mean that we don't know what is going on.

Imagine for a moment that we drive a car into a tree at 60 MPH. We do not have the science that can predict exactly every bend and crease that will occur in every piece of sheet metal of the car, but we know with a very high degree of certainty that the car will be smashed.

Likewise we cannot predict exactly every detail of climate change, but we know with a very high degree of certainty that CO2 absorbs infrared heat energy. This is physics that has been well established for 150 years. So, if we add molecules of CO2 to the atmosphere, those molecules will do what they do, which is to absorb heat energy. This increased heat will cause the atmosphere to warm up.

Humans have predicted that adding CO2 to the atmosphere will cause warming, then added CO2 to the atmosphere, then observed that it has indeed warmed as expected. Hand waving about "still an argument in the data on both sides" does not change the basic physics in the slightest little bit.

Mattimus - ice age cycles and such like are changes in the forcings - orbitally induced change in distribution of incoming solar which set up complex feedbacks and change albedo - when CO2 is low enough.

I fully accept that there are is no way to predict the short term (<30 year) wobbles in surface temperature. No climate modellers is saying you can - only faux skeptics raising a strawman argument. The wobbles are caused by redistribution of heat around the planet. But the total heat content (and thus climate - the line that the wobbles occillilate around) are bound by the energy balance. To change that you have to change one of the forcings. The one that is moving is CO2. And guess what, you do the math and the forcing is the right size.

Of course you cant have certainty in science but conservation of energy is about as good as you can get. And so you demand a full inter-molecular model for cell mechanics before you would take your Dr's advice? The scientific consensus on any subject might not be right but it is the only rational guide to setting policy especially when it is strong.

@2, you are perfectly correct in the fact not everything can be measured. It's called the uncertainty principle and I look forward to any corrections you have to offer as I don't know diddly about Quantum Mechanics but wished i did!

Not everything can be measured because there is something called the real politik of 'limits'... For instance: why do you think you know anything more than anyone elese?

I was composing my comment while your comment at 12 showed up or I would have included a reply in that post.

Planting trees is indeed part of the solutions evaluated by the people who are evaluating "the entire picture of what is going on" such as the people participating in this website.

The know reality is that planting trees and not chopping down trees only partially addresses the magnitude of added CO2 from burning fossil fuels. The IPCC "Mitigation of Climate Change Report" provides a comprehensive summary of the developed understanding regarding afforestation.

By itself, afforestation, even withna stop of all deforestation, would not counteract the production of CO2 from human burning of fossil fuels. It is as simple as that.

Logically, there is a limit to how much plant material can be growing on this amazing planet. So at the end of all the potential afforestation the excess CO2 from continued burning of fossil fuels would continue to grow the problem.

Ending the burning of fossil fuels is understood to be the key component of any mitigation strategy. Forest related action can help or hurt, but it is not a "solution to the identified problem".

Mattimus, to be blunt, we are still arguing about the causes of the observed warming and changing climate mainly because a number of ideologically and financially motivated individuals and organizations have expended a great deal of time, human effort and money to deliberately undermine the science of climate change and spread misinformation and in some cases outright disinformation to the public through the media.

Very few of those individuals are scientists, far fewer still have any expertise in climate science, and to date none of their legitimate science-based objections or alternative hypotheses have been born out, and none of their predictions have stood the test of time in the way that mainstream hypotheses and predictions based on multiple independent lines of evidence and multiple independent modeling efforts have. That alone should tell you something.

Of course this doesn't mean that we understand everything about climate and how it changes, but it does mean that we understand it well enough to know with confidence that we are pushing climate toward a state with potentially very serious negative consequences for humanity. Exactly what those consequences will be, how serious they will be, and when they will emerge is still an active question.

In my earlier comment I did not provide information about your question about pursuing other ways to reduce CO2. I only mentioned afforestation.

The IPCC report I mentioned contains information about other actions. In addition, an SkS article here discusses geoengineering measures.

Since it is not necessary to create the excess CO2 from burning fossil fuels (it is only desired by those who want the ability to obtain maximum benefit any way they can get away with), it is not reasonable or responsible to try to solve such an unnecessarily created problem by taking additional risky action that are unnecessary if the unnecessary creation of the problem is stopped.